net: remove UsingTCPFastOpen() method from StreamSocket class

remoting/protocol/ssl_hmac_channel_authenticator.cc

Index: remoting/protocol/ssl_hmac_channel_authenticator.cc
diff --git a/remoting/protocol/ssl_hmac_channel_authenticator.cc b/remoting/protocol/ssl_hmac_channel_authenticator.cc
index fb91655831dcb18002003dd447e768bfab94c9f6..32fd6c3d2eaf1f3b0c91173c6afc83db52d8d28f 100644
--- a/remoting/protocol/ssl_hmac_channel_authenticator.cc
+++ b/remoting/protocol/ssl_hmac_channel_authenticator.cc
@@ -114,10 +114,6 @@ class NetStreamSocketAdapter : public net::StreamSocket {
     NOTREACHED();
     return true;
   }
-  bool UsingTCPFastOpen() const override {
-    NOTREACHED();
-    return false;
-  }
   void EnableTCPFastOpenIfSupported() override { NOTREACHED(); }
   bool WasNpnNegotiated() const override {
     NOTREACHED();